Author:

Ron Jansen(University of Twente, The Netherlands)

The integration of magnetism and mainstream semiconductor
electronics could
impact information technology in ways beyond imagination. A
pivotal step is
the implementation of spin-based electronic functionality in silicon
devices. Much of the interest in silicon derives from its
prevalence in
semiconductor technology and from the robustness and longevity of
spin as it
is only weakly coupled to other degrees of freedom in the
material. Recently
it has become possible to induce and detect spin polarization in
otherwise
non-magnetic semiconductors (GaAs and Si) using all-electrical
structures,
but so far at temperatures below 150 K and only in n-type
material. The main
challenges are: (i) to design fully electrical silicon-based
spintronic
devices with large spin signals, (ii) to demonstrate device
operation at
room temperature, (iii) to do so for n-type and p-type material,
and (iv) to
find ways to manipulate spins and spin flow with a gate electric
field.
After a brief overview of the state of affairs, our recent
advances in these
areas are described. In particular, we demonstrate room-temperature
electrical injection of spin polarization into n-type and p-type
silicon
from a ferromagnetic tunnel contact, spin manipulation using the
Hanle
effect, and the electrical detection of the induced spin
accumulation. It is
shown that a spin splitting as large as 2.9 meV can be created in
Si at room
temperature, corresponding to an electron spin polarization of
4.6{\%}. The
results open the way to the implementation of spin functionality in
complementary silicon devices and electronic circuits operating
at ambient
temperature, and to the exploration of their prospects as well as
the
fundamental rules that govern their behavior.
\\[4pt]
[1] S.P. Dash, S. Sharma, R.S. Patel, M.P. de Jong and R. Jansen,
Nature \textbf{462}, 491 (2009).

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2010.MAR.H3.2